ODROID HC2 OpenMediaVault LED Control

Maybe it's a little late for an answer regarding your question. Better late than never.

type this as root user:
echo none > /sys/class/leds/blue\:heartbeat/triggerIf you want to turn the LED off automatically in boot process,
add echo none > /sys/class/leds/blue\:heartbeat/trigger in /etc/rc.local file

source:
https://wiki.odroid.com/odroid…lication_note/led_control